Heart Failure (pathology) Flashcards
What is heart failure?
Heart cannot pump blood from both left and right ventricles
What is the outcome of heart failure?
↓ CO and GFR = perceived as decrease in plasma volume —> ↑ Na and H2O (RAAS) + vasoconstriction (SNS) = ↑ plasma volume = heart dilates = ↓ contractility = ↓ CO-> RAAS+ SNS
What is the outcome of left heart failure?
↑pressure in the lungs = pulmonary oedema with transudate – crackles, tachycardia
What causes left heart failure?
Product of LV injury (coronary artery disease, hypertension, cardiomyopathy, valve disease)—> remodelling —> dysfunction —> decreased plasma volume—> induce RAAS+ sympathetic NS
- Salt and water retention - Hypokalaemia + hypomagnesaemia= arrhythmogenic - Vasoconstriction
What is the outcome of right heart failure?
Right heart failure—> blood back into systemic circulation= peripheral oedema + liver central venous congestion (hepatomegaly, peripheral oedema, ↑ JVP, nutmeg liver)
Due to increased hydrostatic pressure (pushing fluid out of capillaries)
Heart failure not a final diagnosis, What underlying causes lead to heart failure?
- Chronic HF due to left ventricular systolic dysfunction (LVSD) due to ischemic heart disease (IHD)
- HF due to severe aortic stenosis
What are the types of heart failure?
- Left ventricular systolic dysfunction (HFrEF)->impaired pumping- reduced ejection fraction
- Left ventricular diastolic heart failure (HFpEF)= impaired filling-preserved ejection fraction- thickened cardiac muscle
What are the risk factors for heart failure (4)?
- Age
- More common in females
- Hypertension -> diastolic dysfunction-> systolic dysfunction
- MI-> directly systolic dysfunction
What causes LVSD?
- MI
- Dilated cardiomyopathy (inherited, toxins, Lyme disease, systemic disease, high BP)
- Aortic disease or mitral regurgitation
Causes of heart failure (6)?
- Valvular disease
- Pericardial constriction/effusion
- Cardiac arrhythmias (tachy/brady)
- MI
- Restrictive cardiopathy
- Right heart failure (primary or secondary to pulmonary hypertension)
What are the symptoms of heart failure (4)?
- SOB
- Fatigue
- Peripheral Oedema
- Reduced exercise capacity
What are the signs of heart failure (7)?
- Oedema
- Tachycardia
- ↑ JVP
- Chest crepitations or effusions
- 3rd heart sound
- Displacement or abnormal apex beat
- Hepatomegaly
What are the 4 grades of the NYHA classification of heart failure?
NYHA classification of HF
- 1 no exercise limitation/ no symptoms
- 2 mild exercise limitation/ comfortable with rest-mild exertion
- 3 moderate exercise limitation/comfortable only at rest
- 4 severe limitation/any activity brings discomfort/ symptoms at rest
(Grading also based on degree of LV impairment/ valve dysfunction + elevation of BNP)
How is heart failure diagnosed?
1) Symptoms + signs of HF (rest or exercise)
+
2) Objective evidence of cardiac dysfunction
3) Response to therapy -Diuretics (FUROSEMIDE)
Which Objective evidence of cardiac dysfunction investigations are used to diagnose heart failure?
- Echocardiography -ESSENTIAL
- Radionuclide ventriculography (RNVG, MUGA)
- MRI
- Left ventriculography In doubtful cases
What % ranges does heart failure range from normal to severe on an echocardiography?
Normal 55-70%
Mild 40-55%
Moderate 30-40%
Severe < 30%
What screening tests are the FIRST line for suspected Heart failure?
- BNP
- ↑BNP= seen in HF= need for echo/cardiac assessment, ↓BNP= exclude HF
- Exclude renal failure, anaemia, thyroid disease (TFTs) electrolytes, autoantibodies, ferritin, serology
- Coronary angio if chest pain
What is the difference between HFrEF and HFpEF?
Both due to LVSD
HFrEF = heart failure with reduced ejection fraction (also known as systolic HF)
HFpEF = heart failure with preserved ejection fraction (diastolic HF)
What is the treatment of heart failure due to LVSD (HFrEF)?
*diuretics in both HFrEF & HFpEF
1 ACE inhibitors (RAMIPRIL) + Beta blockers – only use if patient is stabilised, not in acute HF
- ARBs (no reduction in mortality) if intolerant to ACEi
2 Mineralocorticoid receptor antagonists – SPIRONOLACTONE / EPLERENONE – recommended for ALL HFrEF LVEF ≤ 35% + ACEi & BBs if symptoms continue
3 Angiotensin receptor and neprolysin inhibitor (ARNI)= blocks breakdown of BNP+ boosts endogenous BNP
- VALSARTAN-SACUBITRIL
4 IVABRIDINE (If channel blocker)- only use if stable rhythm and HR ≥ 70
5 DIGOXIN- ↑ Ca2+. In myocytes -> reduce hospitalisation but no effect on mortality
What is the treatment of heart failure due to LVSD (HFpEF)?
- Manage comorbidities (hypertension, atrial fibrillation, IHD, diabetes)
What is monitored closely in heart failure?
Weight
Regular monitoring of weight to determine loss/gain of fluid
